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arXiv · 1205.2898

Universal nonclassicality witnesses for harmonic oscillators

T. Kiesel·W. Vogel
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Abstract

It is shown that a nonclassicality witness, whose expectation value can be measured for all quantum states, can be constructed from every nonclassicality filter. This finding leads to a set of universal witnesses, parameterized by only three real numbers, for the detection of nonclassicality of any quantum state of a harmonic oscillator. An explicit operator expression is given for such a universal witness. The application of the witnesses is demonstrated for a nontrivial example, and its experimental measurement is briefly considered.

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T. Kiesel, W. Vogel. 2012-05-13. Universal nonclassicality witnesses for harmonic oscillators. https://arxiv.org/abs/1205.2898

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